GB2053757A - Lost wax patterns - Google Patents
Lost wax patterns Download PDFInfo
- Publication number
- GB2053757A GB2053757A GB7925125A GB7925125A GB2053757A GB 2053757 A GB2053757 A GB 2053757A GB 7925125 A GB7925125 A GB 7925125A GB 7925125 A GB7925125 A GB 7925125A GB 2053757 A GB2053757 A GB 2053757A
- Authority
- GB
- United Kingdom
- Prior art keywords
- wax
- pattern
- wax pattern
- distortion
- patterns
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C7/00—Patterns; Manufacture thereof so far as not provided for in other classes
- B22C7/02—Lost patterns
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Molds, Cores, And Manufacturing Methods Thereof (AREA)
Abstract
Means for reducing distortion in a wax pattern 10, e.g. for a gas turbine engine nozzle guide comprises moulding at least one wax supporting member 14 into the wax pattern which serves to support that portion 12,13 of the wax pattern liable to distortion. <IMAGE>
Description
SPECIFICATION
Lost wax patterns
This invention relates to wax patterns suitable for use in making castings by the lost wax process and more particularly to such patterns having an ability to resist distortion.
It is well known that it is possible by use of the lost wax process to manufacture castings to extremely close tolerances. This makes the process particularly suitable for producing large quantities of highly accurate castings for use in the manufacture of gas turbine engine components.
The process does however have disadvantages. In particular after the wax pattern has been injected it is removed from the die whilst it is still quite soft. This must be done to prevent the patterns cracking due to contraction of the wax and also to maintain an acceptable production rate. Certain wax patterns due to their relatively thin cross-section or complexity which are known to be susceptible to distortion are therefore placed in "setters" after injection where they are allowed to harden off. The setter is usually manufactured from plaster of paris and consists of a mould which conforms to the desired size and shape of the completed wax pattern.
Any distortion which occurs on the wax pattern after injection will therefore be eliminated by the setter. However it is usual to remove the wax pattern from the setter after approximately one hour so that the setter can be used to accommodate a further wax pattern. However the wax pattern after removal from the setter has a residual memory which remains for about one week, so therefore it is highly likely that the wax pattern will therefore distort again.
One way to overcome this problem is to allow the wax patterns to remain in the setters for a week.
However for mass-produced items this would necessitate an extremely large number of setters which would obviously prove expensive and would also create a considerable storage problem.
An object of the present invention is to provide wax patterns in which the aforementioned problems are substantially eliminated.
According to the present invention means for reducing distortion in parts of wax patterns comprises forming at least one wax supporting member upon the pattern during the wax injection stage, the at least one supporting member serving to restrain the parts of the wax pattern liable to distortion.
Preferably the at least one support can remain as a part of the pattern until after the casting has been made whereupon the excess metal formd by the at least one wax support member may be machined from the finished casting.
Alternatively the supports may be cut from the wax pattern prior to being used to form the ceramic mould for the casting.
For better understanding of the invention an embodiment thereof will be more particularly described by way of example only and with reference to the accompanying drawing in which there is shown a pictorial view of a wax pattern made in accordance with the present invention.
The drawing shows generally at 10 a pictorial view of a wax pattern suitable for manufacturing a gas turbine engine nozzle guide vane which comprises an aerofoil vane portion 11, and radially inner and outer platforms shown at 12 and 13 respectively. As can be seen from the drawing the platform portions 12 and 13 are relatively thin and weak and are obviously liable to distortion at their extremities. The platforms are therefore provided with supporting members 14, 15, 16 and 17 which are cast into the wax pattern during the wax injection stage.
In this example the supporting members 14, 15,16 and 17 are formed such as to simply extend between the two platforms 12 and 13. However in the case of the other shaped castings a supporting member or members may be located in any convenient location.
In certain circumstances it may be convenient to remove the supporting members just prior to the wax pattern being used for manufacturing the mould. In this way the wax pattern is supported for the maximum possible time without the necessity of using "setters". There is therefore little likelyhood of any distortion occurring in the brief time it takes to manufacture the mould from the wax pattern.
Alternatively the supporting members may be left as a portion of the wax pattern and therefore form a part of the resulting mould. It will therefore then be necessary to remove the supporting members from the completed casting by machining.
It will be appreciated that whilst the invention has been described as supporting members used for the manufacture of the nozzle guide vane for a gas turbine engine the scope of the invention is not restricted to such an application. The invention could equally well be utilised in the manufacture of any shape of casting produced by the lost wax process and in which the wax pattern is liable to distortion.
1. Means for reducing distortion in a part or parts of a wax pattern comprising forming at least one wax supporting member upon the pattern during the wax injection stage, the at least one supporting member serving to restrain the parts of the wax pattern liable to distortion.
2. Means for reducing distortion within a wax pattern as claimed in claim 1 in which the at least one support can remain as a part of the pattern until after the casting has been made, whereupon the excess metal formed by the at least one wax support member may be removed from the finished casting.
3. Means for reducing distortion within a wax pattern as claimed in claim 1 in which the at least one support may be cut from the wax pattern prior to it being used to form the ceramic mould for the casting.
4. Means for reducing distortion in a wax pattern as claimed in any preceding claim, substantially as hereinbefore described by way of example only and with reference to the accompanying drawings.
Printed for Her Majesty's Stationery Office by Croydon Printing Company
Limited, Croydon Surrey, 19ûû.
Published bythe Patent Office, 25 Southampton Buildings, London, WC2A 1AY, from which copies may be obtained.
**WARNING** end of DESC field may overlap start of CLMS **.
Claims (4)
1. Means for reducing distortion in a part or parts of a wax pattern comprising forming at least one wax supporting member upon the pattern during the wax injection stage, the at least one supporting member serving to restrain the parts of the wax pattern liable to distortion.
2. Means for reducing distortion within a wax pattern as claimed in claim 1 in which the at least one support can remain as a part of the pattern until after the casting has been made, whereupon the excess metal formed by the at least one wax support member may be removed from the finished casting.
3. Means for reducing distortion within a wax pattern as claimed in claim 1 in which the at least one support may be cut from the wax pattern prior to it being used to form the ceramic mould for the casting.
4. Means for reducing distortion in a wax pattern as claimed in any preceding claim, substantially as hereinbefore described by way of example only and with reference to the accompanying drawings.
Printed for Her Majesty's Stationery Office by Croydon Printing Company
Limited, Croydon Surrey, 19ûû.
Published bythe Patent Office, 25 Southampton Buildings, London, WC2A 1AY, from which copies may be obtained.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB7925125A GB2053757B (en) | 1979-07-19 | 1979-07-19 | Lost wax patterns |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB7925125A GB2053757B (en) | 1979-07-19 | 1979-07-19 | Lost wax patterns |
Publications (2)
Publication Number | Publication Date |
---|---|
GB2053757A true GB2053757A (en) | 1981-02-11 |
GB2053757B GB2053757B (en) | 1983-02-23 |
Family
ID=10506596
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB7925125A Expired GB2053757B (en) | 1979-07-19 | 1979-07-19 | Lost wax patterns |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB2053757B (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0084234A1 (en) * | 1981-12-16 | 1983-07-27 | Vickers Plc | Investment casting process and mould |
US5014763A (en) * | 1988-11-30 | 1991-05-14 | Howmet Corporation | Method of making ceramic cores |
US5126082A (en) * | 1988-11-30 | 1992-06-30 | Howmet Corporation | Method of making ceramic cores and other articles |
EP2241391A1 (en) * | 2009-04-14 | 2010-10-20 | Siemens Aktiengesellschaft | Method for producing a negative mould for casting a turbine rotor and mould for producing a wax model of a turbine rotor |
FR3076752A1 (en) * | 2018-01-15 | 2019-07-19 | Safran Aircraft Engines | METHOD FOR MAKING A MULTI-PALE MODEL, TOOLING AND ASSEMBLY OF A MULTI-PALE MODEL AND A HOLDING ELEMENT |
CN113664147A (en) * | 2021-08-02 | 2021-11-19 | 安徽应流航源动力科技有限公司 | Blade wax pattern wax-spraying 3D printing deformation prevention process |
CN114523070A (en) * | 2022-03-01 | 2022-05-24 | 中国航发北京航空材料研究院 | Deformation prevention control method for crown turbine blade casting |
-
1979
- 1979-07-19 GB GB7925125A patent/GB2053757B/en not_active Expired
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0084234A1 (en) * | 1981-12-16 | 1983-07-27 | Vickers Plc | Investment casting process and mould |
US5014763A (en) * | 1988-11-30 | 1991-05-14 | Howmet Corporation | Method of making ceramic cores |
US5126082A (en) * | 1988-11-30 | 1992-06-30 | Howmet Corporation | Method of making ceramic cores and other articles |
EP2241391A1 (en) * | 2009-04-14 | 2010-10-20 | Siemens Aktiengesellschaft | Method for producing a negative mould for casting a turbine rotor and mould for producing a wax model of a turbine rotor |
WO2010118960A1 (en) * | 2009-04-14 | 2010-10-21 | Siemens Aktiengesellschaft | Method for producing a negative mold for casting a turbine blade and mold for producing a wax model of a turbine blade |
FR3076752A1 (en) * | 2018-01-15 | 2019-07-19 | Safran Aircraft Engines | METHOD FOR MAKING A MULTI-PALE MODEL, TOOLING AND ASSEMBLY OF A MULTI-PALE MODEL AND A HOLDING ELEMENT |
US10682685B2 (en) | 2018-01-15 | 2020-06-16 | Safran Aircraft Engines | Method of making a multi-vane model, tooling, and an assembly comprising a multi-vane model and a holder element |
CN113664147A (en) * | 2021-08-02 | 2021-11-19 | 安徽应流航源动力科技有限公司 | Blade wax pattern wax-spraying 3D printing deformation prevention process |
CN113664147B (en) * | 2021-08-02 | 2023-10-20 | 安徽应流航源动力科技有限公司 | Anti-deformation process for wax spraying and 3D printing of blade wax mould |
CN114523070A (en) * | 2022-03-01 | 2022-05-24 | 中国航发北京航空材料研究院 | Deformation prevention control method for crown turbine blade casting |
CN114523070B (en) * | 2022-03-01 | 2022-12-16 | 中国航发北京航空材料研究院 | Deformation prevention control method for casting shrouded turbine blade |
Also Published As
Publication number | Publication date |
---|---|
GB2053757B (en) | 1983-02-23 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19930719 |